Fig. 1: Modulating transformation of DODA via junction sequence design.

a Top and side view of a free-stranding Holliday junction, which exhibits the X-shaped conformation with an inter-helix angle of ~60°. b Generally, the four arms of a junction are confined into a plane by the surrounding DNA helices in a DNA nanostructure. c Simplified energy model for DODA transformation. d Schematics showing the step-by-step transformation of the DODA used in this work. e Detailed view of a junction in the DODA under conformation I and II. The blue strands and gray strands represent scaffold DNA and staple DNA, respectively. The four base pairs at the junction are highlighted to illustrate the different stacking patterns in junction configuration i and configuration ii.